Fibre Channel is an American National Standards Institute (ANSI) set of standards directed to a high performance serial transmission protocol. Generally, Fibre Channel merges the advantages of channel technology with network technology to provide an input/output (I/O) interface which meets the requirements of both channel and network users.
Fibre Channel provides several important advantages over prior art interface schemes. Fibre channel provides high transmission bandwidths (presently up to about 4 gigabits (1012) per second), which significantly improves computer-to-computer and computer-to-data storage device transfers. Fibre Channel utilizes fiber optic technology, which significantly expands possible interconnect distances between devices (up to about six miles), reduces noise and simplifies cabling requirements. Fibre Channel is also high level protocol independent, which allows a number of different protocols to be concurrently supported over the same network.
Serial data transfers using Fibre Channel are carried out in the form of frames. A command request from an initiator device to a target device for user data will typically result in the transmission of multiple, successive data frames from the target device, with the user data provided in the payload portions of the frames. Devices also transmit status frames, which are typically single frames with multiple status words as the payload. Among other uses, status frames are typically appended to the end of a data frame transmission to indicate the completion of the data transfer event.
While Fibre Channel represents a significant improvement in the transmission of computerized data, there remains a continual need for further improvements in the art with regard to the sorting and prioritizing of multiple pending frame transfers in a Fibre Channel or other serial interface environment. It is to such improvements that the claimed invention is directed.